Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
va cao » va cac, va co, va dao
vi va » vi van, vai va, vu va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu va cao ((xuc van) or (duc van)) hanh vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu va cao ((xuc van) OR (duc van)) hanh vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (lang xa)) hoi. hieu va cao ((xuc van) or (duc van)) hanh vi va triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu va cao ((xuc van) or (duc van)) hanh vi va triet*.